The present invention relates to engines and in particular to a detachable cylinder assembly for use in a cam-drive engine and to solenoid operated valves and a catalytic converter for use in this type of engine.
Operable configurations of the reciprocating-piston internal combustion engine have been known for more than a century. In that time substantial developments have occurred that have resulted in ever higher levels of efficiency and reliability in engines being produced commercially. Despite this long legacy of improvement, these engines are still subject to wear and degraded operation with extended use. Once they have achieved long operating lives these engines commonly require internal repairs in the form of cylinder wall boring or honing and piston ring replacement.
Today most reciprocating-piston internal combustion engines are built around a cylinder block housing into which are machined either the cylinder bores directly or receivers for cylinder liners. In either case, the previously mentioned internal repairs require substantial disassembly of the engine and often removal of the entire engine from its operating environment. This holds true even when the repairs are to be carried out on only one or a small number of the cylinders in a multi-cylinder engine. The removal from service and the total labor required to carry out the repairs represents a substantial cost to the engine""s user in particular where the engine is being used in a commercial application.
There exists a class of engines known as xe2x80x9ccam-drivexe2x80x9d or xe2x80x9cswash platexe2x80x9d engines. These engines are often described as xe2x80x98barrelxe2x80x99 engines because many have a cylinder block that is substantially the shape of a large diameter, short cylinder. Although, it is well known that the xe2x80x9ccam-drivexe2x80x9d or xe2x80x9cswash platexe2x80x9d engines have a number of benefits, the barrel configuration of the cylinder block common to this type of engine can cause difficulty in performing some maintenance or repair operations on these engines. In particular, in many implementations of the xe2x80x9ccam-drivexe2x80x9d or xe2x80x9cswash platexe2x80x9d engine the cylinder block is a large mono-block or split-block which can require significant and complex disassembly in order to remove the pistons or to gain access to the inner cylinder walls as exemplified by the engine in U.S. Pat. No. 4,492,188 issued Jan. 8, 1985. For many of these engines it is difficult to imagine how they could receive cylinder maintenance (such as piston or ring replacement, cylinder boring or honing; etc.) without the complete removal of the engine assembly from its operating environment. Therefore, although xe2x80x9ccam-drivexe2x80x9d or xe2x80x9cswash platexe2x80x9d engines are known to have numerous operating advantages over the more common crank-drive engines they are not superior in terms of ease of internal engine repair.
Growing concerns over environmental issues has led to the widespread adoption of legislation limiting exhaust emissions from internal combustion engines. One of the most significant technologies that has been adopted to help meet these emissions restrictions is the use of catalytic converters. Although catalytic converts have proven effective at reducing emissions in normal operation they do suffer from a significant shortcoming. That is, they are relatively ineffective until a minimum operating temperature has been achieved. This has led to the introduction of numerous ancillary solutions (e.g. supplemental fast warm-up converters, heating elements in the converters, etc.) which address the period of time between engine start-up and attainment of a sufficient operating temperature in the catalytic converter. These solutions add significant cost, complexity and weight to the emissions control systems.
The cam-drive engine and the cylinder assembly of the present invention are structured to permit installation and removal of the cylinder assembly to/from the engine without requiring disassembly of the cylinder assembly. The solenoid and cylinder pressure operated valves of the present invention facilitate the installation and removal of the cylinder assembly by eliminating the need for mechanical valve actuation. The catalytic converter of the present invention provides for fast warm-up of the catalyst by placing the converter proximate to the cylinder assembly.
In accordance with one aspect of the present invention, a cylinder assembly for detachable mounting on a cam-drive engine core having a drive shaft, a power plate affixed to said drive shaft, a power plate housing substantially supporting said drive shaft and said power plate, a cylinder connecting rod connected to said power plate, and a cylinder assembly mounting position connected to said power plate housing, said cylinder assembly comprising: a cylinder housing with attachment apparatus for detachably mounting at said mounting position, a cylinder head assembly affixed to an end of said cylinder housing, a piston positioned inside of said cylinder housing, a piston connecting pin connected to said piston, and an aperture in said cylinder housing through which said piston connecting pin is accessible for detachable connection to said cylinder connecting rod; wherein said cylinder assembly can be attached or detached to said engine core as an assembled unit.
In accordance with another aspect of the present invention, a cylinder assembly for detachable mounting on a cam-drive engine core having a drive shaft, a power plate affixed to said drive shaft, a power plate housing substantially supporting said drive shaft and said power plate, a cylinder connecting rod connected to said power plate, and a cylinder assembly mounting position connected to said power plate housing, said cylinder assembly comprising: a cylinder housing with attachment apparatus for detachably mounting at said mounting position, first and second cylinder head assemblies, one affixed to each end of said cylinder housing, first and second pistons positioned inside of said cylinder housing, a piston connecting rod connected at one end to said first piston and at another end to said second piston, a piston connecting pin connected to said piston connecting rod, and an aperture in said cylinder housing through which said piston connecting pin is accessible for detachable connection to said cylinder connecting rod, wherein said cylinder assembly can be attached or detached to said engine core as an assembled unit.
In accordance with a further aspect of the present invention, a cam-drive engine core for detachable mounting of a cylinder assembly having a cylinder housing with attachment apparatus for detachable mounting, a head assembly affixed to an end of said cylinder housing, a piston positioned inside of said cylinder housing, a piston connecting pin connected to said piston, and an aperture in said cylinder housing through which said piston connecting pin is accessible, said engine core comprising: a drive shaft, a power plate affixed to said drive shaft, a power plate housing substantially supporting said drive shaft and said power plate, a cylinder connecting rod, connected to said power plate, for detachable connection to said piston connecting pin, and a cylinder assembly mounting position, for detachably receiving said cylinder assembly attachment apparatus, connected to said power plate housing; wherein said cylinder assembly can be attached or detached to said engine core as an assembled unit.
In accordance with yet another aspect of the present invention, a cam-drive engine comprising: an engine core having a drive shaft, a power plate affixed to said drive shaft, a power plate housing substantially supporting said drive shaft and said power plate, a cylinder connecting rod connected to said power plate, and a cylinder assembly mounting position connected to power plate housing, and a cylinder assembly having a cylinder housing with attachment apparatus for detachable mounting at said mounting position, a head assembly affixed to an end of said cylinder housing, a piston positioned inside of said cylinder housing, a piston connecting pin connected to said piston, and an aperture in said cylinder housing through which said piston connecting pin is accessible for connection to said cylinder connecting rod; wherein said cylinder assembly can be attached or detached to said engine core as an assembled unit.
In accordance with still another aspect of the present invention, a cam-drive engine comprising: an engine core having a drive shaft, a power plate affixed to said drive shaft, a power plate housing substantially supporting said drive shaft and said power plate, a plurality of cylinder connecting rods connected to said power plate, and a plurality of cylinder assembly mounting positions connected to power plate housing, and a plurality of cylinder assemblies each having a cylinder housing with attachment apparatus for detachable mounting at one of said plurality of mounting positions, a head assembly affixed to an end of said cylinder housing, a piston positioned inside of said cylinder housing, a piston connecting pin connected to said piston, and an aperture in said cylinder housing through which said piston connecting pin is accessible for connection to one of said plurality of cylinder connecting rod; wherein each of said plurality of cylinder assemblies can be individually attached or detached to said engine core as an assembled unit.
In accordance with yet a further aspect of the present invention, a solenoid operated intake valve comprising: a gas flow port, a plunger, a resilient means biasing said plunger into a closed position sealing-off said gas flow port, means for locking said plunger in said closed position, and a solenoid for driving said plunger into an open position exposing said gas flow port.
In accordance with still a further aspect of the present invention, a pressure differential and solenoid operated exhaust valve comprising: a gas flow port, a plunger, a resilient means damping said plunger as it is driven in to an open position, exposing said gas flow port, by a pressure differential across said plunger, a solenoid for driving said plunger into a closed position sealing-off said gas flow port, and means for locking said plunger in said closed position.
In accordance with still another aspect of the present invention, a catalytic converter for proximate location to a cylinder assembly comprising: a substantially cylindrical inner body, a substantially cylindrical outer body whose radius is greater than that of said inner body, a cylinder assembly mounting position, to which said cylinder assembly can be affixed, disposed on the outer surface of said outer body, a plurality of supporting webs that extend from the inner body to the outer body, a catalytic carrier disposed within a cavity formed between said inner body, said outer body and said supporting webs, a catalyst disposed on said catalyst carrier, a first end cap sealing a first end of said cavity, an entry port in said first end cap to admit exhaust gases from said cylinder assembly to said cavity, via a exhaust runner; a second end cap sealing a second end of said cavity, an exit port connecting said cavity to the interior of said inner body, and an exhaust port in said first end cap through which exhaust gases in said inner body can flow; whereby the catalyst is effective at reducing the emissions of exhaust gases from said cylinder assembly circulated via said entry port, through said cavity to said exit port.
Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.